I'm over in Afghanistan right now, and one of the most popular lights is the Rayovac three way headlamp. It has a white LED, two red LEDs and a halogen bulb. Very good combination of lights for many tactical and non-tactical uses. The Inova microlights are also extremely popular and are almost never on the shelves at the PX here. If they do get a shipment, the lights are only on the shelves for an hour or less.
There are a couple models of Surefire lights here, the C2 Centurion and one other much higher priced one. Those lights don't move as well and are always on the racks. Mini mags are always in abundant supply, so I guess those are the light of last resort for the troops. I brought my Inova 24/7 in OD green and the troops love it. Several have ordered ones as well (from BrightGuy, on my recommendation). If there was some way to get Arcs in the PX system, you can bet they would fly off the shelves. What do you think, Peter?
LED lights seem to be the way to go for deployments, as they run forever on a set of batteries and provide sufficient light for most tasks. The Surefires are popular with the killers and they usually trick out their M4 rifles with every kind of light, scope and laser pointer imaginable. As an EDC though, I'd go with the Arc or the CMG Infinity or Ultra.
Also, don't forget the troops in Afghanistan. With everything going on in Iraq, the guys in Afghanistan are on the back burner, so to speak. But believe me, there are constant operations here, thousands of soldiers deployed and the need for a light better than a MX-991/U or mini Mag ever present.